Clomiphene- chest tightness?

Hi- I'm in third round of Clomiphene...one more cycle planned if needed.
Last 2 days I have had tightness in my sternum area of my chest- not heavy but enough to notice it. Tried to book a Dr appointment but they are full up for two days :/ trying not to be a hyperchondriac but wondering what is causing it? Was going to go to Bikram (hot) yoga tonight but going to give it a miss...
Has anyone else experienced chest tightness as a side effect and what action did you take if any?